{{Short description|Austrian aircraft engine}} {{Use dmy dates|date=April 2023}} {{Use American English|date=April 2023}} <!-- This article is a part of [[Wikipedia:WikiProject Aircraft]]. Please see [[Wikipedia:WikiProject Aircraft/page content]] for recommended layout. --> {{infobox aero engine | name=Rotax 915 iS | alt = See caption | image=Rotax_915_iS,_AERO_2018,_Friedrichshafen_(1X7A4431).jpg | caption= |engine_type=[[Piston]] [[aircraft engine]] |manufacturer=[[Rotax]] |designer= |national_origin=[[Austria]] |first_run=2014 |major_applications=[[Issoire APM 40 Simba|Issoire APM 41 Simba 915iS]] |produced=2017–present<ref name="flyrotax.com">{{cite web|title=ROTAX 915 IS/ISC - Rotax Aircraft Engines|url=https://www.flyrotax.com/produkte/detail/rotax-915-is-isc.html|website=www.flyrotax.com|accessdate=31 January 2018|language=en}}</ref> |number_built= |developed_from=[[Rotax 912]] |variants_with_their_own_articles= [[Rotax 916 iS]] }} The '''Rotax 915 iS''' is an [[Austria]]n [[aircraft engine]], produced by [[Rotax]] of [[Gunskirchen]] for use in [[ultralight aircraft]], [[homebuilt aircraft]], [[light-sport aircraft]], small [[helicopters]] and [[gyroplane]]s. The engine was [[Type certificate|type certified]] in 2017.<ref name="avweb.com">{{cite web|url=http://www.avweb.com/avwebflash/news/Rotax-Announces-New-135-hp-Turbocharged-Engine-224487-1.html|title=Rotax Announces New 135-hp Turbocharged Engine|work=AVweb|date=21 July 2015|accessdate=22 July 2015}}</ref><ref>{{cite web|url=https://www.rotax-owner.com/en/rotax-blog/item/43-915is|title=Rotax-Owner.com - ROTAX 915 IS: BRP UNVEILS A NEW TURBOCHARGED ROTAX AIRCRAFT ENGINE|work=Rotax-Owner|accessdate=22 July 2015}}</ref>

The engine was first publicly displayed at [[AirVenture]] in July 2015<ref name="avweb.com"/> and first flown in March 2016.<ref>{{cite web|url=http://www.avweb.com/avwebflash/news/Rotax-Updates-915iS-Progress-225991-1.html|title=Rotax Updates 915iS Progress|work=AVweb|date=6 April 2016|accessdate=7 April 2016}}</ref>

In January 2016 the engine was named AVweb's "Best New Engine" of 2015.<ref>{{cite web|url=http://www.avweb.com/blogs/insider/AVwebs-Stuff-of-the-Year-225403-1.html|title=AVweb's Stuff of the Year|work=AVweb|date=29 December 2015|accessdate=2 January 2016}}</ref>

==Design and development== The Rotax 915 iS is a four-cylinder [[four-stroke]], [[horizontally-opposed]], [[turbocharged]], air and liquid-cooled, gasoline engine design, with a mechanical gearbox [[reduction drive]]. The turbocharger has a compression ratio of 3.5:1 and the engine will have a critical altitude of {{convert|15000|ft|m|0|abbr=on}}. It employs dual electronically controlled fuel injection, using dual channel [[Rockwell Collins]] ECUs, with dual ignition and produces {{convert|141|hp|kW|0|abbr=on}} for take-off and {{convert|135|hp|kW|0|abbr=on}} continuous. The engine can produce rated power up to {{convert|15000|ft|m|0|abbr=on}} and has a ceiling of {{convert|23000|ft|m|0|abbr=on}}.<ref name="flyrotax.com"/><ref name="avweb.com"/><ref name="avweb.com1"/>

The engine is based on the [[Rotax 912]], but differs in that it has fuel injection, a reinforced crankshaft, new pistons, a new gearbox and a turbocharger. [[Time between overhaul]]s was expected to eventually be raised to 2000 hours with operational experience, but started at 1200 hours.<ref name="avweb.com"/><ref name="avweb.com1">{{cite web|url=http://www.avweb.com/avwebflash/news/Rotax-915iS-Sport-Moves-Closer-To-Market-226660-1.html|title=Rotax 915iS Sport Moves Closer To Market|work=AVweb|date=26 July 2016|accessdate=28 July 2016}}</ref><ref name="flyrotax.com"/>

The design entered production in the second half of 2017. The [[European Aviation Safety Agency]] certified the Rotax 915 iSc3 A on 14 December 2017 and the Rotax 915 iSc3 B on 4 January 2018.<ref name="EASA">{{cite web|url = https://www.easa.europa.eu/sites/default/files/dfu/TCDS_E%20121_Issue10_20180104_1.0.pdf|title = Type Certificate Data Sheet No, E.121 for Piston Engines Rotax 912 series |access-date = 31 January 2019|author=[[European Aviation Safety Agency]]|work = www.easa.europa.eu|date = 4 January 2018}}</ref>

In December 2021 the option to replace the 12V electrical system with a 24V one was introduced. The 24V version of the engine is designated the 915iS C24 for the non-certified version and the 915iSc C24 certified version.<ref name="OConnor22Dec21">{{cite web|url= https://www.avweb.com/ownership/engines/rotax-introduces-24v-option-for-915is/|title= Rotax Introduces 24V Option For 915iS|access-date= 24 December 2021|last= O'Connor|first= Kate|work= AVweb|date= 22 December 2021|archive-url= https://archive.today/20211224125952/https://www.avweb.com/ownership/engines/rotax-introduces-24v-option-for-915is/?MailingID=799&utm_source=ActiveCampaign&utm_medium=email&utm_content=FAA+To+Investigate+Santa+Clara+Safety+Concerns,+Appareo+Systems+Acquired+By+Global+Agricultural+Firm&utm_campaign=FAA+To+Investigate+Santa+Clara+Safety+Concerns,+Appareo+Systems+Acquired+By+Global+Agricultural+Firm+-+FRIDAY,+December+24,+2021|archive-date= 24 December 2021|url-status= live}}</ref> <!-- ==Operational history== -->

==Variants== ;Rotax 915iS :Base version with a 12V electrical system ;Rotax 915iS C24 :Non-certified model with 24V electrical system<ref name="OConnor22Dec21"/> ;Rotax 915iSc C24 :Certified model with 24V electrical system<ref name="OConnor22Dec21"/> <!-- ==Survivors== --> <!-- Engines on display== -->

==Applications == *[[Pro.Mecc Freccia Anemo]] *[[Blackshape Prime]] *[[Horizontec Halcón|Horizontec Halcón 2.1]] *[[Issoire APM 40 Simba|Issoire APM 41 Simba 915iS]] *[[Progressive Aerodyne SeaRey]] *[[Sling Aircraft Sling TSi]] *[[Swiss Excellence Risen]] *[[Flying Legend Tucano Replica]] *[https://www.bristell.com/bristell-b23-turbo/ Bristell B23-915 Turbo] *[https://www.tlsportaircraft.com/sparker/ TL Sparker] *[https://www.tlsportaircraft.com/stream/ TL Stream]

==Specifications (915 iS) == {{pistonspecs| |ref=AVweb<ref name="avweb.com"/> and manufacturer's website<ref name="flyrotax.com" /> |type=four-cylinder, four-stroke, horizontally-opposed, geared aircraft engine |bore={{convert|84.0|mm|in|1|abbr=on}} |stroke={{convert|61.0|mm|in|1|abbr=on}} |displacement={{convert|1352|cc|cuin|1|abbr=on}} |length=<!-- {{convert||mm|in|1|abbr=on}} --> |diameter= |width=<!-- {{convert||mm|in|1|abbr=on}} --> |height=<!-- {{convert||mm|in|1|abbr=on}} --> |weight={{convert|84.6|kg|lb|1|abbr=on}} dry |valvetrain= |supercharger= |turbocharger= with a compression ratio of 3.5:1 |fuelsystem=dual channel [[Rockwell Collins]] ECUs |fueltype=high-octane automotive gasoline |oilsystem= |coolingsystem=liquid and air |power={{convert|141|hp|kW|0|abbr=on}} for take-off, {{convert|135|hp|kW|0|abbr=on}} continuous |specpower= |compression= |fuelcon= |specfuelcon=280–310 [[gram|g]]/([[kilowatt|kW]]·[[hour|h]]) at 5,500&nbsp;rpm |oilcon= |power/weight=0.73 hp/lb (1.19 kW/kg)

|designer= |reduction_gear=mechanical gear type

|general_other= |components_other= |performance_other= }}

==See also== {{aircontent <!-- include as many lines are appropriate. additional lines/entries with carriage return. --> |see also= |related=<!-- related developments --> |similar aircraft=<!-- similar or comparable aircraft --> |lists= *[[List of aircraft engines]] }}

==References== {{Reflist}}

==External links== {{Commons category|Rotax 915}} *{{Official website|https://www.beachrayasia.com/product/rotax-915-i-141/}} *[http://www.avweb.com/videos/Video-Rotax-Introduces-the-915-iS-224498-1.html Video: Rotax Introduces the 915 iS] on AVweb

{{Rotax aeroengines}}

[[Category:Rotax engines]] [[Category:2010s aircraft piston engines]] [[Category:Boxer engines]] [[Category:Liquid-cooled aircraft piston engines]] [[Category:Four-cylinder engines]]